use readv reader by default

common/buf/io.go

@@ -59,7 +59,20 @@ func NewReader(reader io.Reader) Reader {
 		return mr
 	}
 
-	return newReaderPlatform(reader)
+	if useReadv {
+		if sc, ok := reader.(syscall.Conn); ok {
+			rawConn, err := sc.SyscallConn()
+			if err != nil {
+				newError("failed to get sysconn").Base(err).WriteToLog()
+			} else {
+				return NewReadVReader(reader, rawConn)
+			}
+		}
+	}
+
+	return &SingleReader{
+		Reader: reader,
+	}
 }
 
 // NewWriter creates a new Writer.

common/buf/io_highend.go

@@ -1,23 +0,0 @@
-// +build 386 amd64 s390 s390x
-
-package buf
-
-import (
-	"io"
-	"syscall"
-)
-
-func newReaderPlatform(reader io.Reader) Reader {
-	if useReadv {
-		if sc, ok := reader.(syscall.Conn); ok {
-			rawConn, err := sc.SyscallConn()
-			if err != nil {
-				newError("failed to get sysconn").Base(err).WriteToLog()
-			} else {
-				return NewReadVReader(reader, rawConn)
-			}
-		}
-	}
-
-	return NewBytesToBufferReader(reader)
-}

common/buf/io_lowend.go

@@ -1,13 +0,0 @@
-// +build mips mipsle mips64 mips64le arm arm64
-
-package buf
-
-import (
-	"io"
-)
-
-func newReaderPlatform(reader io.Reader) Reader {
-	return &SingleReader{
-		Reader: reader,
-	}
-}

common/buf/reader.go

@@ -4,7 +4,6 @@ import (
 	"io"
 
 	"v2ray.com/core/common"
-	"v2ray.com/core/common/bytespool"
 	"v2ray.com/core/common/errors"
 )
 
@@ -24,66 +23,6 @@ func readOne(r io.Reader) (*Buffer, error) {
 	return nil, newError("Reader returns too many empty payloads.")
 }
 
-const largeSize = 128 * 1024
-
-// BytesToBufferReader is a Reader that adjusts its reading speed automatically.
-type BytesToBufferReader struct {
-	io.Reader
-	buffer []byte
-}
-
-// NewBytesToBufferReader returns a new BytesToBufferReader.
-func NewBytesToBufferReader(reader io.Reader) Reader {
-	return &BytesToBufferReader{
-		Reader: reader,
-	}
-}
-
-func (r *BytesToBufferReader) readSmall() (MultiBuffer, error) {
-	b, err := readOne(r.Reader)
-	if err != nil {
-		return nil, err
-	}
-	if b.IsFull() && largeSize > Size {
-		r.buffer = bytespool.Alloc(Size + 100)
-	}
-	return NewMultiBufferValue(b), nil
-}
-
-func (r *BytesToBufferReader) freeBuffer() {
-	bytespool.Free(r.buffer)
-	r.buffer = nil
-}
-
-// ReadMultiBuffer implements Reader.
-func (r *BytesToBufferReader) ReadMultiBuffer() (MultiBuffer, error) {
-	if r.buffer == nil || largeSize == Size {
-		return r.readSmall()
-	}
-
-	nBytes, err := r.Reader.Read(r.buffer)
-	if nBytes > 0 {
-		mb := NewMultiBufferCap(int32(nBytes/Size) + 1)
-		common.Must2(mb.Write(r.buffer[:nBytes]))
-		if nBytes == len(r.buffer) && nBytes < int(largeSize) {
-			bytespool.Free(r.buffer)
-			r.buffer = bytespool.Alloc(int32(nBytes) + 100)
-		} else if nBytes < Size {
-			r.freeBuffer()
-		}
-		return mb, nil
-	}
-
-	r.freeBuffer()
-
-	if err != nil {
-		return nil, err
-	}
-
-	// Read() returns empty payload and nil err. We don't expect this to happen, but just in case.
-	return r.readSmall()
-}
-
 // BufferedReader is a Reader that keeps its internal buffer.
 type BufferedReader struct {
 	// Reader is the underlying reader to be read from

common/buf/reader_test.go

@@ -1,9 +1,7 @@
 package buf_test
 
 import (
-	"bytes"
 	"io"
-	"runtime"
 	"testing"
 
 	. "v2ray.com/core/common/buf"
@@ -11,32 +9,6 @@ import (
 	. "v2ray.com/ext/assert"
 )
 
-func TestAdaptiveReader(t *testing.T) {
-	if runtime.GOARCH != "amd64" {
-		t.Skip("Smart reader only works on highend devices.")
-		return
-	}
-
-	assert := With(t)
-
-	reader := NewReader(bytes.NewReader(make([]byte, 1024*1024)))
-	b, err := reader.ReadMultiBuffer()
-	assert(err, IsNil)
-	assert(b.Len(), Equals, int32(Size))
-
-	b, err = reader.ReadMultiBuffer()
-	assert(err, IsNil)
-	assert(b.Len(), Equals, int32(8*1024))
-
-	b, err = reader.ReadMultiBuffer()
-	assert(err, IsNil)
-	assert(b.Len(), Equals, int32(32*1024))
-
-	b, err = reader.ReadMultiBuffer()
-	assert(err, IsNil)
-	assert(b.Len(), Equals, int32(128*1024))
-}
-
 func TestBytesReaderWriteTo(t *testing.T) {
 	assert := With(t)
 
@@ -87,8 +59,8 @@ func TestBytesReaderMultiBuffer(t *testing.T) {
 func TestReaderInterface(t *testing.T) {
 	assert := With(t)
 
-	assert((*BytesToBufferReader)(nil), Implements, (*io.Reader)(nil))
-	assert((*BytesToBufferReader)(nil), Implements, (*Reader)(nil))
+	assert((*ReadVReader)(nil), Implements, (*io.Reader)(nil))
+	assert((*ReadVReader)(nil), Implements, (*Reader)(nil))
 
 	assert((*BufferedReader)(nil), Implements, (*Reader)(nil))
 	assert((*BufferedReader)(nil), Implements, (*io.Reader)(nil))

common/buf/readv_reader.go

@@ -140,7 +140,12 @@ var useReadv = false
 func init() {
 	const defaultFlagValue = "NOT_DEFINED_AT_ALL"
 	value := platform.NewEnvFlag("v2ray.buf.readv").GetValue(func() string { return defaultFlagValue })
-	if value != defaultFlagValue && (runtime.GOOS == "linux" || runtime.GOOS == "darwin") {
+	switch value {
+	case defaultFlagValue, "auto":
+		if (runtime.GOARCH == "386" || runtime.GOARCH == "amd64" || runtime.GOARCH == "s390x") && (runtime.GOOS == "linux" || runtime.GOOS == "darwin") {
+			useReadv = true
+		}
+	case "enable":
 		useReadv = true
 	}
 }